Earthquakes are most dangerous near areas where people live. Deaths and injuries are not caused by movement of the ground, but buildings collapsing and fires.

Earthquake damage can be reduced A powerful

earthquake (magnitude of 8 or higher) can release more energy than 1 million weak earthquakes.

The first scale of earthquake magnitude was developed by Charles Richter and Beno Gutenburg

Earthquake damage can be reduced The Richter scale measures

how fast the ground moves at a seismic station

Earthquake damage can be reduced Most scientists

currently use the moment magnitude scale

Both ricther and moment scale show a top value of 10, but neither has a maximum value.

The moment magnitude scale is more accurate for larger earthquakes

Earthquake damage can be reduced Movement of blocks

of rock along a fault on either side can raise, lower or tilt the ground surface(This can collapse buildings)

Many buildings collapse and in the process gas lines,power lines, and water lines can be damaged

Earthquake damage can be reduced In the San Francisco

earthquake of 1906, 90% of the buildings collapsed

Earthquake damage can be reduced Earthquakes can also cause

landslides to occur A landslide is movement of

rocks and soil down a hill or a mountain

Structures either sink with the soil or flow away with it

Earthquake damage can be reduced A tsunami can also occur as a

result of an earthquake, volcanic eruption or landslide.

A tsunami is a water wave that can rise more than a 20 story building

Earthquake damage can be reduced A tsunami can be a single

wave or several waves of different heights

In deep water a tsunami can reach speeds of about 430 mph

Earthquake damage can be reduced In 1946 a

earthquake hit Alaska, a tsunami resulted and the highest wave was 55 feet high and it killed 159 people

The Pacific Tsunami Warning center was established in hawaii in 1949

Earthquake damage can be reduced Scientists havent figured out

earthquakes similar to the weather they can only make longterm predictions

Scientists study stress along fault lines

Earthquake damage can be reduced Signs that give scientists clues

are: Tilts or changes in rock Slow movement or stretching

in rock The development of small

cracks in the ground

Earthquake damage can be reduced The best way to

prevent death and injuries is to build structures meant to withstand some earthquakes

Base isolators are built into buildings, they are flexible an absorb the shock

Earthquake damage can be reduced Buildings are also

built on a moat which will let the building shake more gently

Cross braces are also added to help the structure keep it’s shape while shaken